Acquisition of Rickettsia rickettsii (Rickettsiales: Rickettsiaceae) by Haemaphysalis longicornis (Acari: Ixodidae) through co-feeding with infected Dermacentor variabilis (Acari: Ixodidae) in the laboratory.

Haemaphysalis longicornis (Neumann) is an invasive ixodid tick originating from eastern Asia which recently has become established in the United States. In its native range, this tick can transmit several pathogens to animals and humans, but little is known about its ability to acquire and transmit pathogens native to the United States. Geographic overlap with ticks such as Dermacentor variabilis (Say), a known vector of Rickettsia rickettsii, makes investigation into the interactions between H. longicornis and D. variabilis of interest to the public health community. Previous studies have shown that H. longicornis can serve as a competent vector of R. rickettsii under laboratory settings, but there is little information on its ability to acquire this pathogen via other biologically relevant routes, such as co-feeding. Here, we assess the ability of H. longicornis nymphs to acquire R. rickettsii through co-feeding with infected D. variabilis adults on a vertebrate animal model under laboratory conditions. The median infection prevalence in engorged H. longicornis nymphs across 8 cohorts was 0% with an interquartile range (IQR) of 4.13%. Following transstadial transmission, the median infection prevalence in flat females was 0.7% (IQR = 2.4%). Our results show that co-feeding transmission occurs at low levels in the laboratory between these 2 species. However, based on the relatively low transmission rates, this may not be a likely mechanism of R. rickettsii introduction to H. longicornis.

Patterns and Ecological Mechanisms of Tick-Borne Disease Exposure Risk in Acadia National Park, Mount Desert Island, Maine, United States.

National parks are unique and significant vector-borne pathogen transmission settings, engaging over 300 million people in outdoor recreation per year. In this study, we integrated vector surveys and ecological habitat feature data in spatial models to characterize tick-borne disease exposure risk in Acadia National Park (ANP), Maine. To determine the broad-scale patterns of blacklegged tick Ixodes scapularis Say (Acari: Ixodidae) densities in ANP, we conducted host-seeking tick collections at 114 sites across the park over two years. Using these tick survey data and geospatial landscape feature data (i.e., land cover, elevation, forest patch size, and aspect) we developed a random forest model of nymphal tick density. We found that host-seeking tick density varies significantly across the park and is particularly high in areas characterized by deciduous forest cover and relatively low elevation. To explore potential fine-scale ecological drivers of tick density spatial patterns, we quantified microclimate conditions, host activity, and vegetation characteristics at a subset of 19 sites. We identified significant differences in microclimate conditions but not host activity or vegetation metrics across broad-scale landscape feature classes. Mean temperature and mean humidity were correlated to nymphal densities and therefore may provide a mechanistic link between landscape features and blacklegged tick densities. Finally, we detected multiple tick-borne pathogens in both ticks and small mammals sampled in ANP, including Borrelia burgdorferi, Babesia microti, and Anaplasma phagocytophilum. Our findings demonstrate the value of using ecological metrics to estimate vector-borne disease exposure risk and provide insight into habitat characteristics that may drive tick-borne disease exposure risk.

Interactions between sympatric invasive European fire ants (Myrmica rubra) and blacklegged ticks (Ixodes scapularis).

The blacklegged tick (Ixodes scapularis) and the invasive European fire ant (Myrmica rubra) are both expanding throughout their sympatric range in coastal New England. Ixodes scapularis is the primary vector of the bacterium Borrelia burgdorferi, which is the causative agent of Lyme disease, and Mount Desert Island, Maine, home to Acadia National Park, currently is affected by a high Lyme disease burden. Ticks have many natural predators, including ants, although no previous studies have investigated interactions between these two species. To test the hypothesis that the presence of M. rubra alters I. scapularis abundance, we collected ticks by drag-sampling at eight ant-infested sites and eight uninfested control sites in Acadia National Park. We found that nymph density was significantly higher at ant-infested sites, while larval density was significantly higher at control sites. In addition, we conducted a laboratory bioassay to measure M. rubra aggression against I. scapularis larvae, nymphs, and adults and Dermacentor variabilis adults, and found that ant aggression was significantly higher against D. variabilis adults than I. scapularis adults. Our findings support the hypothesis that M. rubra has divergent effects across I. scapularis life stages, and we discuss possible ecological mechanisms, including optimal microclimate and predation, that could promote density of nymphs while inhibiting density of larvae.

Lyme Disease Risk of Exposure to Blacklegged Ticks (Acari: Ixodidae) Infected with Borrelia burgdorferi (Spirochaetales: Spirochaetaceae) in Pittsburgh Regional Parks.

Lyme disease is the most commonly reported vector-borne illness and sixth most commonly reported notifiable infectious disease in the United States. The majority of cases occur in the Northeast and upper-Midwest, and the number and geographic distribution of cases is steadily increasing. The blacklegged tick (Ixodes scapularis Say) is the principal vector of the Lyme disease spirochete (Borrelia burgdorferi sensu stricto) in eastern North America. Although Lyme disease risk has been studied in residential and recreational settings across rural to urban landscapes including metropolitan areas, risk within U.S. cities has not been adequately evaluated despite the presence of natural and undeveloped public parkland where visitors could be exposed to B. burgdorferi-infected I. scapularis. We studied the occurrence of I. scapularis and infection prevalence of B. burgdorferi in four insular regional parks within the city of Pittsburgh to assess Lyme disease risk of exposure to infected adults and nymphs. We found that the density of I. scapularis adults (1.16 ± 0.21 ticks/100 m2) and nymphs (3.42 ± 0.45 ticks/100 m2), infection prevalence of B. burgdorferi in adults (51.9%) and nymphs (19.3%), and density of infected adults (0.60 ticks/100 m2) and nymphs (0.66 ticks/100 m2) are as high in these city parks as nonurban residential and recreational areas in the highly endemic coastal Northeast. These findings emphasize the need to reconsider, assess, and manage Lyme disease risk in greenspaces within cities, especially in high Lyme disease incidence states.

Understanding human management of automation errors.

Automation has the potential to aid humans with a diverse set of tasks and support overall system performance. Automated systems are not always reliable, and when automation errs, humans must engage in error management, which is the process of detecting, understanding, and correcting errors. However, this process of error management in the context of human-automation interaction is not well understood. Therefore, we conducted a systematic review of the variables that contribute to error management. We examined relevant research in human-automation interaction and human error to identify critical automation, person, task, and emergent variables. We propose a framework for management of automation errors to incorporate and build upon previous models. Further, our analysis highlights variables that may be addressed through design and training to positively influence error management. Additional efforts to understand the error management process will contribute to automation designed and implemented to support safe and effective system performance.

Understanding challenges in the front lines of home health care: a human-systems approach.

A human-systems perspective is a fruitful approach to understanding home health care because it emphasizes major individual components of the system - persons, equipment/technology, tasks, and environments - as well as the interaction between these components. The goal of this research was to apply a human-system perspective to consider the capabilities and limitations of the persons, in relation to the demands of the tasks and equipment/technology in home health care. Identification of challenges and mismatches between the person(s) capabilities and the demands of providing care provide guidance for human factors interventions. A qualitative study was conducted with 8 home health Certified Nursing Assistants and 8 home health Registered Nurses interviewed about challenges they encounter in their jobs. A systematic categorization of the challenges the care providers reported was conducted and human factors recommendations were proposed in response, to improve home health. The challenges inform a human-systems model of home health care.

How Do Older Adults Manage Osteoarthritis Pain? The Need for a Person-Centered Disease Model.

In the United States, chronic pain affects at least 116 million Americans, differentially impacting older adults. One of the leading causes of pain for older adults is osteoarthritis. This disease affects approximately 14% of the United States population and can cause disability and mobility problems, in addition to having a high cost for the healthcare system. The methods individuals use to manage their pain are contingent upon their model of the disease (e.g., their beliefs about osteoarthritis pain management). The purpose of the present investigation was to: 1) understand what variables older adults with osteoarthritis believe impact pain, and 2) understand current approaches for self-management of osteoarthritis pain. We conducted structured interviews with eight older adults who have osteoarthritis. The interviews revealed current approaches in pain management, as well as gaps in knowledge. We propose an expansion of the idea of a general disease model for pain management that is patient-centered, allowing for personal customization of factors for reducing pain and increasing successful pain-management.

CHALLENGES OF TRAINING OLDER ADULTS IN A HOME HEALTH CARE CONTEXT.

The health care domain is experiencing a shift from traditional hospital-based care to care delivered in a patient's home setting. Although home health care provides many benefits, it creates new challenges and difficulties for professional caregivers (e.g., registered nurses) who are performing complex medical tasks without the support often present in a health care environment. In addition to performing these tasks themselves, registered nurses are also responsible for training patients to perform many of these tasks, which may include using medical devices and managing complex medication regimens. The purpose of this research was to identify and systematically categorize the issues facing registered nurses (RNs) when training older adult patients. Eight RNs participated in individual structured interviews wherein they were asked to describe the difficulties and frustrations associated with training older adult patients to use medical devices and manage medication independently. The data were categorized as patient-related, RN-related, or situation-related issues. The results highlight the complexity of training device use and medication management, as well as the needs of RNs for forms of additional support in training older adult patients.

The smooth (tractor) operator: insights of knowledge engineering.

The design of and training for complex systems requires in-depth understanding of task demands imposed on users. In this project, we used the knowledge engineering approach (Bowles et al., 2004) to assess the task of mowing in a citrus grove. Knowledge engineering is divided into four phases: (1) Establish goals. We defined specific goals based on the stakeholders involved. The main goal was to identify operator demands to support improvement of the system. (2) Create a working model of the system. We reviewed product literature, analyzed the system, and conducted expert interviews. (3) Extract knowledge. We interviewed tractor operators to understand their knowledge base. (4) Structure knowledge. We analyzed and organized operator knowledge to inform project goals. We categorized the information and developed diagrams to display the knowledge effectively. This project illustrates the benefits of knowledge engineering as a qualitative research method to inform technology design and training.

Understanding the effect of workload on automation use for younger and older adults.

OBJECTIVE: This study examined how individuals, younger and older, interacted with an imperfect automated system. The impact of workload on performance and automation use was also investigated. BACKGROUND: Automation is used in situations characterized by varying levels of workload. As automated systems spread to domains such as transportation and the home, a diverse population of users will interact with automation. Research is needed to understand how different segments of the population use automation. METHOD: Workload was systematically manipulated to create three levels (low, moderate, high) in a dual-task scenario in which participants interacted with a 70% reliable automated aid. Two experiments were conducted to assess automation use for younger and older adults. RESULTS: Both younger and older adults relied on the automation more than they complied with it. Among younger adults, high workload led to poorer performance and higher compliance, even when that compliance was detrimental. Older adults' performance was negatively affected by workload, but their compliance and reliance were unaffected. CONCLUSION: Younger and older adults were both able to use and double-check an imperfect automated system. Workload affected how younger adults complied with automation, particularly with regard to detecting automation false alarms. Older adults tended to comply and rely at fairly high rates overall, and this did not change with increased workload. APPLICATION: Training programs for imperfect automated systems should vary workload and provide feedback about error types, and strategies for identifying errors. The ability to identify automation errors varies across individuals, thereby necessitating training.

Challenges for Home Health Care Providers: A Needs Assessment.

Home health care provides substantial benefits over traditional, hospital-based health care, such as supporting older adults' independence and quality of life, as well as being more cost effective. This aspect of the health care industry could be enhanced through increased technological supports. When providing health care in a home setting, caregivers are faced with many challenges that impede their ability to perform their jobs. Technological interventions have the potential to alleviate many of these challenges. However, to achieve this potential, new technologies must be created to meet the needs of home health care providers. To date, these providers' specific and most critical needs are not thoroughly understood. This understanding can be gained by conducting a detailed needs assessment that captures the common challenges and difficulties that home health care providers encounter. We conducted a needs assessment comprising three phases: 1) an extensive literature review; 2) subject matter expert interviews; and 3) structured interviews with home health care providers. We identified several significant sources of frustration and difficulty faced by providers including: medical device usage; patient education; family involvement; provider isolation; and barriers to communication. This analysis provides an understanding of the challenges confronting home health care providers that can provide guidance for interventions. Future home health care technology can be developed to specifically target these workers' most urgent needs and allow them to perform their jobs with greater ease.

NEEDS ASSESSMENT FOR CERTIFIED NURSING ASSISTANTS PROVIDING PERSONAL CARE.

Home health care allows individuals to receive care in a home setting rather than a medical facility. This increasingly popular alternative to health care has many benefits; however, providing health care in a home setting involves unique challenges and difficulties for the health care providers, such as certified nursing assistants (CNAs). Human factors interventions and technological supports may ease difficulties home health care providers experience performing caregiving tasks. However, for such interventions to be effective there is a need to understand patient care within the context of a home environment. The purpose of this research was to conduct a needs assessment to identify 1) personal caretask characteristics, including the context in which they are carried out, and 2) challenges encountered during these tasks. Eight CNAs participated in structured interviews where in they were asked to describe difficulties and frustrations experienced when performing the tasks of toileting, bathing, and transfer. The results were categorized as patient- or provider-based difficulties, as well as along dimensions related to the environment, device design, and social influences. These data provide an understanding of the complexity of each task, and a means of highlighting areas of difficulty to provide guidance for designers of assistive technologies and other supportive interventions.

Older Adults' Needs for Home Health Care and the Potential for Human Factors Interventions.

Demand for home health care is expected to increase as more people are living longer and because older adults rely on home health services to a greater extent than any other population (CDC, 2000). This paper provides an overview of older adults' home health care needs as well as guidance for potential human factors interventions to reduce medical errors and improve quality of care and independence for older patients. Factors discussed include reducing transition and handoff errors, ensuring proper use of medical devices, managing medication, and optimizing home health settings. The importance of considering the role of normal age-related changes in abilities when evaluating patients' needs is highlighted. The goal of this analysis is to provide guidance for human factors interventions in home health care.